"It still surprises me that Democrats in the Senate are opposing a bill that they don't oppose," Mulvaney said, noting that the funding bill before lawmakers is clean -- with no unrelated riders --and that it includes an extension of the Children's Health Insurance Program that has bipartisan support.

"They don't oppose anything in the bill but they are opposing the bill," Mulvaney said

The shutdown is set to begin at midnight

"They don't oppose anything in the bill but they are opposing the bill," Mulvaney said. "We don't want this. We do not want a shutdown," Mulvaney said.

Senate Democrats have insisted that as part of the government funding process lawmakers resolve the legal status of 700,000 people brought to the US illegally as children who had been protected under the Obama era Deferred Action for Childhood Arrivals program. President Donald Trump rolled back those protections, but lawmakers at the time said they would work to restore them.